Google Apps is now G Suite. Same service, new name. More about the name change.

About Email Log Search

You can sift through the delivery logs for your domains and evaluate message delivery using Email Log Search in the Google Admin console. The reports help you track down missing messages, such as those quarantined as spam or otherwise routed incorrectly. You can also use the tool to determine message IP addresses and troubleshoot how policies affect mail flow.

Available only for G Suite Business and G Suite. Tool not available to resellers when accessing a resold domain Admin console using the reseller console.​